Pfizer is in advanced discussions with a property consortium to sell its UK research facility in Sandwich, Kent.
The company said in February 2011 that it would close the plant, where erectile dysfunction drug Viagra was developed, leading to the loss of 2,400 jobs.
It was later announced that the number of layoffs would be reduced, with 650 workers to be retained at the site, and 250 transferred to other Pfizer R&D sites.
A Pfizer spokesperson said: “Following a structured selection process, Pfizer has entered into a period of legal exclusivity with a consortium led by London & Metropolitan and financed by a major European institutional real estate investor, for the sale of the Discovery Park campus in Sandwich, Kent.
“This announcement is a positive milestone in the transition of Discovery Park to becoming an R&D led multiple-use campus with Enterprise Zone status.”
Conservative MP for Thanet South, Laura Sandys, welcomed the news.
Speaking to the BBC, she said: "It means we'll be able to market the Discovery Park very effectively and ensure that we've got a vision for the Enterprise Zone that will attract new jobs and new companies."
Sandys also said London and Metropolitan had a “very clear vision about having a strong life-science park that will attract people internationally" following discussions with the potential buyers.
Pfizer intends to keep using a number of the Discovery Park facilities on a leased basis, but is looking for a buyer to take over the majority of the site, which occupies around 70 hectares and provides about 280,000 sq m of accommodation, including specialist laboratories.
Several ex-Pfizer employees at the site have gone on to set up their own research ventures.
In September, 2011, seven former Pfizer staff members helped set up The Research Network, which CEO Andrew McElroy described as a firm would help biotech and pharmaceutical companies find the right partners for outsourcing research productivity.
Separately, former Pfizer researchers have launched new companies based at BioCity Nottingham, one of Europe's largest bioscience business centres.